1. Field of the Invention
The present invention relates to a substrate transport hand and a substrate transport robot.
2. Description of the Background Art
A substrate transport hand including receiving portions capable of receiving substrates thereon is known in general. Japanese Patent Laying-Open No. 2001-274232 discloses a substrate transport hand including a pair of arm portions (hand body portions) and a plurality of wafer support members provided on each of the pair of arm portions. This substrate transport hand is so formed that the pair of arm portions are movable in directions approaching to and separating from each other. Each wafer support member is formed stepwise, to be capable of receiving substrates on first and second grasp portions (receiving portions) provided on the upper and lower steps thereof respectively. In order to receive the corresponding substrate on the first grasp portion provided on the upper step, the substrate transport hand adjusts the position of the wafer support member so that an end of the substrate comes into contact with the first grasp portion by moving the pair of arm portions thereby controlling the interval between the arm portions. In order to receive the corresponding substrate on the second grasp portion provided on the lower step, further, the substrate transport hand adjusts the position of the wafer support member so that an end of the substrate comes into contact with the second grasp portion by moving the pair of arm portions thereby controlling the interval between the arm portions. Thus, the substrate transport hand can support the substrates on different positions with the two different grasp portions (receiving portions).